Before they became the stars of their own main event, when the trainers of Manny Pacquiao and Brandon Rios spoke to the press, it was about their fighters and their plans for Saturday night's contest here at the Venetian Macao. And when they were questioned, it was to inquire about their plans and strategies for that fight, and to ascertain how their charges were feeling. But even then, the signs of tension between the camps percolated beneath the surface.

On Monday, Robert Garcia, chief second for Rios, spoke with a few reporters in his fighter's hotel suite. Pacquiao, he was at pains to point out, "has been a great champion, considered perhaps one of the best in history, and we might not ever again see a fighter accomplish what he has accomplished." But, he added, "we've seen the last two years, the last two fights, there are some differences, there are some changes, and especially his last fight when he got knocked out. We don't know, nobody knows, how that really affected him. We've seen other fighters, and I would say nine out of 10 are never the same, but we don't know."

Then there came a point in the discussion when Garcia, who was 2012's Boxing Writers Association of America trainer of the Year, turned his focus unbidden to Pacquiao's trainer Freddie Roach.

"I went out on my own, with my own gym, five years ago, and in the last five years everything that I've done, that I've accomplished with my team, especially the last two years, has been great," he began. "For Roach to be worried about, 'I want to prove that I'm the best trainer. I want to prove that my gym is the best,' I'd be ashamed to say that about a 38 year old who started five years ago. I think they're the ones who have everything to lose."

So was Roach -- who won the same Trainer of the Year award five times before Garcia assumed his mantle -- as tweaked by his young rival's success as Garcia claimed? Asked about it the next day, the veteran cornerman didn't exactly seem consumed with anxiety, but he did acknowledge that, "I'd like to beat him, yeah," and referenced Ring Magazine listing Roach as being "out" and Garcia being "in" in its year-end list.

Which brings us to the present, and the scene Wednesday morning when Roach entered the gym area beneath the Venetian Arena that the two camps are sharing during fight week. Rios and Garcia have the gym booked from 9 to 11 each day, and Pacquiao and Rios from 11 to 4. (That, in itself, was the source of some tension, given that Roach made the first pick: "Five hours?" exclaimed Garcia. "Who trains for five hours?") But on this day, Team Rios was still in the gym past 11 – a consequence, they said, of having to take 15 minutes to shoot an interview for ESPN's SportsCenter, and Roach wanted them out.

The result would not have been out of place in a schoolyard face-off.

"Get the fuck out."

"I'm not going anywhere."

"Piece of shit."

"Don't call me a piece of shit."

There was shoving, pushing, the hurling of at least one racial epithet, some apparent mocking of Roach's Parkinson's disease, a kick to Roach's stomach, and a near-brawl that was only quelled by the intervention of security. It was altogether unedifying, but for the rest of the day it was pretty much the only topic of conversation around the media room. Videos of the clash, filmed from different angles, were dissected with an intensity normally associated with scholars of the Zapruder film.

Later in the evening, at the final press conference, neither trainer took the opportunity to walk things back. Garcia said not to trust any video of the scuffle except for one. "I want to invite everyone to go toESNewsReporting.com, because that's where you will see exactly what happened, " he said. When it was his turn at the podium Roach countered, "Yeah, go watch that website because that's his friend and he edited it for him. How dumb is that?" Promoter Bob Arum joked that he would be bringing in Judge Judy to settle the matter. Viewers will get a chance to decide for themselves when 24/7 airs Thursday night.

But if writing an account of the shenanigans felt oddly like detailing the settling of grievances after recess, the conflict was real, the volcanic release of simmering tensions. Whether it will affect the fighters, or the fight, is another matter.